iphone 5 powers up only with Home+power key combination

[seitsme]

My iphone 5, was a secondhand device bought a while ago as a replacement to other model i have had.
It has the latest ios on it.

It was working ok despite it came in contact with water and then was cleaned with isopropanol and started up ok. The charging dock was also replaced from another iphone all were ok.

I remember when phone was charging with usb went upto 86% then stopped charging.
When i re-mounted the phone to charge it to see if goes tupto 100% it worked.

The phone possibly shutdown to approx 5 Celcious.

Next morning i tried to use power button when i saw it was off. It did not startup at all.
I decided to use the Restart or force quit combination (pressing power button and home button).

Phone started ok and since then i have no problem, but i think it will shut down again if battery
is left to low percentage and will not startup.

Any clues where the problem is please.

 

[AxlTJ]

Were all replaced but the battery? Might need a new battery.

 

[seitsme]

Were all replaced but the battery? Might need a new battery.

I replaced the battery yesterday, and started ok, i charged it fully and at night, again about 5C shut down.
It did not shut down ie the time i was listening music, but a while after i stopped using the phone. Strange isnt it...
In the morning did not open with power button but i did the restart combination and started up.

Not sure if this is something the phone does to ie match the current battery charge levels with its counter and for a reason cant make it through....

Since yesterday it did not shut down again, but might do soon and dont know where to look for help or part to repair further.

I saw a video about a power button flex cable and switch but not sure if this 100% messes up with the power (why to shut down the phone - it would be a problem starting up only i presume...)

 

[Lekro]

If you can reset the phone with the home and power button then they are working fine. Check the mute switch and the volume buttons. If all fine then the top flex is ok.

Random shutdowns and rebooting with a reset is a sign of water damage. If there was no ultrasonic cleaning of the board then probably by this time it started oxidising under the metal shields on the motherboard.

You need to inspect the board.

 

[AxlTJ]

As Lekro said, inspect the board. All the possible causes have been eliminated but the board. Have the board inspected.

 

[seitsme]

the phone at the moment does not shut down after ie 8 hours. but ie after 3 days at random times.
Then i power on, does nothing. I then use the home and power button and boots ok. Then works ok.
I also did one reset or restart when battery was at about 1% just in case i had to recalibrate battery
and nothing unusual i have to say.

when reboots as above, the battery indicator is at the level when phone was shut down.
I cleaned the board x2 times with isopropanol or whatever is called since last shut down.

There was no ultrasonic cleaning as was a DIY solution for cost issues etc. Volume, mute etc are working ok.
I presume power is ok as it restarts with combination keys

I presume board issue. Still not sure. I also ordered some new cables for board just in case i need them.

 

[Lekro]

Is the battery draining any faster than it used to be or does the phone get warm?

 

[seitsme]

Lekro: i changed the battery with a new non original from web. Battery i think behaves ok now.
Still not sure because when i bought the BATT i have had to fully charge it and when i initially installed it, was about 65% which the seller told me should be like that. Then i went upto 100% and restarted phone etc. Since then when iphone goes off i see battery is in the same level approx it was before shutdown.

The phone though gets warm i noticed that also, its 64gb

 

[Lekro]

Try to determine if the battery side or the motherboard side is getting warm. If mobo then it could be a short to ground somewhere. Try to locate the source of excess heat.

Does the board have any greenish stain on it?

 

[seitsme]

Try to determine if the battery side or the motherboard side is getting warm. If mobo then it could be a short to ground somewhere. Try to locate the source of excess heat.

Does the board have any greenish stain on it?

For the first not sure how to do that. If i remove the LCD and start the phone or remove LCD with phone working
not sure if will be nice idea.

Board has no greenish stains at all. At the moment.

 

[Lekro]

You can do it with the phone fully assembled, just touch the back and feel where is the heat source, which side.

Or you if want to measure more precisely, then you can lift up the display without disconnecting it and touch the board if there is any concentrated heat source.

 

[seitsme]

You can do it with the phone fully assembled, just touch the back and feel where is the heat source, which side.

Or you if want to measure more precisely, then you can lift up the display without disconnecting it and touch the board if there is any concentrated heat source.

Hm, ok will do that, altough with case close when i listen to music, i feel the back side area, where the motherboard is approx, is more warm.

Would you suggest to do another a 3rd, isopropanol cleaning and leave the phone for example, for 8 hours in this liquid just in case it cleans better debris from past laundry... lol

 

[Lekro]

I can only suggest ultrasonic cleaning. You could just take it to a repair shop and have them do it for you, shouldn’t be an expensive service.

If that’s not an option then go ahead with your own way but it won’t be as effective.

 

[seitsme]

I have to look for such service. Never heard of it before.
What i also noticed is that iphone goes off almost always after i save a lengthy recording with the memo recorder (apple) app ie over 25min. but even with 60% batt available.

 

[Lekro]

Can’t really say anything more. It can be the power management IC or something around that circuit.

What I would do is try with an another battery if ultrasonic cleaning can’t be done.

 

[seitsme]

when i change batteries it startsup OK but after a while with a new replacement it shuts down...
i think i will get a new device to be sure it works correctly...

 

[Lekro]

I’m sorry it didn’t work out for you.

This is definitely a motherboard issue and considering the age of the device it is not worth it to proceed with such repair on it (except as a hobby).

 

[seitsme]

true... will start selling spares now my camera flash brings that error -disable ...bug- message....
thanks